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From: gillies@m.cs.uiuc.edu
Newsgroups: comp.sys.next
Subject: Re: backup of hard disk
Message-ID: <61300044@m.cs.uiuc.edu>
Date: 11 Nov 90 02:20:00 GMT
References: <13089@chaph.usc.edu>
Lines: 25
Nf-ID: #R:chaph.usc.edu:13089:m.cs.uiuc.edu:61300044:000:1295
Nf-From: m.cs.uiuc.edu!gillies    Nov 10 20:20:00 1990


I don't own a NeXT, but let me say, NeXT is very intelligent to
implement a 2.88Mb floppy drive in their machine.  With such a device,
backup is just 37-112 floppies away (depending on whether you have a
105Mb or a 330Mb drive).

Believe it or not, this is realistic to do.  I back up an 80Mb Mac
disk with 800K floppies.  It's a royal drag to stuff 70 floppies in
the machine (I have about 57Mb in use), but was not too bad putting 30
floppies in, when the machine was young.

I have always believed in some formula for personal computers --

(1) Floppy drive should be as large as main memory (NeXT did all they
    could to achieve this, given current standards).
(2) All of main memory should be readable in approximately 1 second.
(3) Hard disk should be configured to be 50% larger than necessary to
    hold all applications and data files.  This is because of the high
    cost of garbage collection (deleting unneeded files).  It is
    counterproductive to manage a disk that is constantly near the
    threshold of being full.
(4) Virtual Memory only doubles main memory; beyond this, performance
    suffers too much to make virtual memory worthwhile.
(5) The CPU should execute 5 IPS for every bit of data displayed on
    the screen (the 68040 NeXT does 8 IPS for the b/w display).